Consulting group PricewaterhouseCoopers has said it is seeking to recruit almost 300 people.
250 of these will be part of its graduate recruitment programme, while it is also looking for 40 professionally qualified people to fill "strategic roles" across the firm.
PwC Senior Partner Ronan Murphy said the level of recruitment was a reflection of the demand for the firm's services.
The new jobs for professionals will be in its Dublin office at Spencer Dock, but positions are also available in Cork, Limerick, Galway, Kilkenny, Waterford and Wexford.
Meanwhile, computer game development company BioWare has announced plans to recruit a further 200 workers for its new operation in Galway, bringing to 400 the number that will be employed there.
At the official opening of a new global customer service centre this afternoon, the company said it had chosen Ireland as a location because it had a steady supply of well-educated people.
It also pointed to State supports and said there was a great partnership between BioWare and the Government, which would allow the company to expand further here in the coming years.
In excess of 100 people are already employed at the company's Irish base and recruitment for the remaining jobs has commenced.
The centre in Galway will provide 24/7 support for gamers in the English, French and German speaking worlds.
Speaking at the opening, the Taoiseach, Enda Kenny said the Government hoped that the investment by BioWare would encourage other game development companies to look at Ireland.
Mr Kenny said there were already 30 core companies operating in the video game industry here.
He said the Government planned to introduce new measures to expand the number of jobs in the sector and to make Ireland the first choice for companies looking to expand.
When BioWare bosses announced plans to open their first European customer base, they said Galway was chosen because it had the right mix of solid technology infrastructure and international recruitment opportunities.
Dr Ray Muzyka and Dr Greg Zeschuk said the new facility provided BioWare with greater proximity to European online players.
IDA Ireland Chief Executive Barry O'Leary said Galway had the skills base and expertise for this vibrant digital media sector.
Separately, department store Brown Thomas plans to advertise 150 job vacancies tomorrow at its Brown Thomas and BT2 stores on Grafton Street, at BT2 Dundrum and BT2 Blanchardstown, all in Dublin.
The temporary full-time and part-time positions will cover the Christmas and New Year periods.
